Process Refractometer PR-43 Instruction Manual - K · PDF fileProcess Refractometer PR-43 ... P4-001 PR-43 REFRACTOMETER M-12-8 pin, A-code, M non-Ex PR-43 REFRACTOMETER ... tionisturnedoff(section2.3.2)

$Page 1: Process Refractometer PR-43 Instruction Manual - K · PDF fileProcess Refractometer PR-43 ... P4-001 PR-43 REFRACTOMETER M-12-8 pin, A-code, M non-Ex PR-43 REFRACTOMETER ... tionisturnedoff(section2.3.2)$
Process Refractometer PR-43

Document/Revision No. IM-EN-PR43GEN: Rev. 1.04Effective: June 8, 2017

Instruction Manual

Document/Revision No. IM-EN-PR43GEN/1.04 Effective: June 8, 2017

General safety considerations

The process medium may be hot or otherwise hazardous. Use shields and

protective clothing adequate for the processmedium - donot rely on avoid-

ance of contact with the process medium.

Precautions when removing a refractometer from the process line :

• Check first that the process line is depressurized and drained.

• Ensure you stay clear of any possible spillage and you have a clear emer-

gency escape path.

It is the user’s responsibility to followmanufacturer’s safety and operating instructions.

The client’s organization has the responsibility to develop and maintain occupational

safety and create a safety culture where individuals are expected to follow safety in-

structions at all times. Any negligence towards safety instructions or failure to comply

with safe practices should not be tolerated. It is the manufacturer’s responsibility to

produce goods that are safe to use when instructions are followed.

Disposal

When wishing to dispose of an obsolete refractometer or any parts of a

refractometer, please observe local and national regulations and require-

ments for the disposal of electrical and electronic equipment.

Symbols and terms used in this manual:

This indicates a warning. It provides safety precaution information needed to

avoid injury while operating the refractometer system.

This indicates that something is important for the operation of the refractome-

ter system.

Note. Notes contain additional information and hints.

This product manual is delivered to the end user with a K-Patents product. Information

in this manual is subject to change without notice. When the manual is changed, a

revised copy is published at http://www.kpatents.com/

Warranty

All K-Patents products are guaranteed to be free of material or workmanship defects.

K-Patents provides a limited warranty that covers the repair or replacement, without

charge, of any defected product or part that occurs within two (2) years from the date

of delivery. The repair can only be done by nearest authorized K-Patents repair facility.

It is the buyer’s responsibility to select the product material and to ensure that the ma-

terial is satisfactory for the intended service conditions. It is themanufacturer’s respon-

sibility to ensure that a material conforms to the specification. Therefore the warranty

admitted by K-Patents does not cover for example shortened life cycle or breakdown

of an instrument in where the shortened life cycle or breakdown is due to customer’s

material choice.

Warranty does not cover normal wear and tear of the product over time, or any prod-

ucts that are handled, installed or used against manufacturer’s guidance.

Fullwarranty information is available in the Support sectionofhttp://www.kpatents.com/

Please note that prior to shipping any products or items to K-Patents, a Request for

Return Materials Authorization (RMA) must be filled in and submitted to K-Patents

Order Handling department. The RMA form is available at http://www.kpatents.com/

in the Support section.

Table of contents

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 Refractometer connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.1 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.2 mA output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.3 Ethernet connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.3.1 IP settings for the PR-43 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2.3.2 IP settings for a stand-alone computer . . . . . . . . . . . . . . . . . . . . . . 6

2.3.3 Configuring a network of refractometers . . . . . . . . . . . . . . . . . . . . 7

2.3.4 Testing the Ethernet connection . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

2.3.5 Troubleshooting the connection . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3 Web interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3.1 Main page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.2 Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

3.3 Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

3.3.1 Measuring field samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

3.3.2 Optical image . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

3.4 Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4 Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1 Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1.1 Initial check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1.2 mA check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1.3 Calibration check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.2 Viewing refractometer status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

5 Configuration and calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

5.1 Configuring the refractometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

5.1.1 Signal damping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

5.1.2 Configuring mA output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

5.1.3 Skip count . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5.2 Calibrating the concentration measurement . . . . . . . . . . . . . . . . . . 23

5.2.1 The chemical curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

5.2.2 Field calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

© Copyright K-Patents 2017. All rights reserved.

6 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.1 Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.1.1 Message HIGH INTERNAL HUMIDITY . . . . . . . . . . . . . . . . . . . . . . . 26

6.1.2 Message HIGH INTERNAL TEMP . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.2 Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.2.1 Message OUTSIDE LIGHT ERROR or OUTSIDE LIGHT TO PRISM . . . 26

6.2.2 Message NO OPTICAL IMAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.2.3 Message PRISM COATED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.2.4 Message LOW IMAGE QUALITY . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.2.5 Message NO SAMPLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.2.6 Message TEMP MEASUREMENT FAULT . . . . . . . . . . . . . . . . . . . . . 28

6.2.7 Concentration drift during NORMAL OPERATION . . . . . . . . . . . . . . 28

6.3 Diagnostic messages table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

7 Principle of measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

8 Ethernet protocol specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

8.1 Communication protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

8.1.1 Request format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

8.1.2 Response format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

8.1.3 Request and response errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

8.2 Request-response pair specification . . . . . . . . . . . . . . . . . . . . . . . . . 33

8.2.1 NULL message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

8.2.2 Protocol version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

8.2.3 Refractometer information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

8.2.4 Measurement results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

8.3 Error message specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

A PR-43 refractometer field calibration form . . . . . . . . . . . . . . . . . . . . . . . . . . 35

B EU declaration of conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

PR-43 instruction manual


1 Introduction 1


1 Introduction

The K-Patents in-line process refractometer is an instrument for measuring liquid con-

centration in the process line. The measurement is based on the refraction of light in

the process medium, an accurate and safe way of measuring liquid concentration. See

Chapter 7 for more information on the measurement principle.

The PR-43 refractometers come in three standard packages: a stand-alone refractome-

ter withWeb user interfaceWI, a refractometer with Compact user interface CI and 1-4

refractometers with Multichannel user interface MI.

Web user interface WI is for direct control system integration in applications where no

industrial computer or monitoring display is required (see Chapters 2, 4 and 3). Com-

pact user interface provides a local or remote display with the same information as

WI (See Compact user interface CI manual). Multichannel user interface provides high

performance industrial computing e.g. for multiple connectivity and wash control (see

Multichannel user interface MI manual).

2 PR-43 instruction manual


2 Refractometer connections

The refractometer has an Ethernet connection for digital data acquisition and configu-

ration. The standard connection cable is made with an 8-pin industrial M12 connector

in the refractometer end. For more information on the cables, see the manual for your

refractometer model.

2.1 Power supply

The PR-43 refractometer requires a 24 V DC power supply (allowable tolerance is

±10%). The current consumption of the refractometer is less than 80mA. The power

supply should be shielded from external voltage surges.

2.2 mA output

The PR-43 refractometer can be connected with just mA output. The analogue connec-

tion transmits measurement signal only.

10m (33ft)

90m (295ft)

180m (590ft)

200m (656ft)

P4-001

PR-43 REFRACTOMETERM-12-8 pin, A-code, Mnon-Ex




max. 90m (295ft) max. 90m (295ft)

max. 90m (295ft)

10m (33ft)

PR-8430Platform 4 cableM12-8 pin, A-code, F+MEthernet, mA, 24V



PR-8660Platform 4 cable extenderM12-8 pin, A-code, F+M

PR-8431Split cable M12M12-8 pin, A-code, FEthernet (M12-4 pin, D-code,M)mA, 24V

PR-8431Split cable M12M12-8 pin, A-code, FEthernet (M12-4 pin, D-code,M)mA, 24V1m (3ft)

PR-8431Split cable M12M12-8 pin, A-code, FEthernet (M12-4 pin, D-code,M)mA, 24V1m (3ft)

max. 200m (656ft)

PR-8680M12-8 pin, A-code, FField plug

PR-8432Power supply and mA output cable

Refractometer only Cables

M

M M

M MM

F

F

F

F

F

F F

Figure 2.1 Analogue connection

If the refractometer is connected with Split cable PR-8431, both mA and Ethernet out-

puts are available.

2 Refractometer connections 3


10m

(33f

t)

90m

(295

ft)

180m

(590

ft)

200m

(656

ft)

P4-0

01

PR-4

3 RE

FRAC

TOM

ETER

M-1

2-8

pin,

A-c

ode,

Mno

n-Ex

PR-4

3 RE

FRAC

TOM

ETER

M-1

2-8

pin,

A-c

ode,

Mno

n-Ex

PR-4

3 RE

FRAC

TOM

ETER

M-1

2-8

pin,

A-c

ode,

Mno

n-Ex

PR-4

3 RE

FRAC

TOM

ETER

M-1

2-8

pin,

A-c

ode,

Mno

n-Ex

max

. 90m

(295

ft)

max

. 90m

(295

ft)

max

. 90m

(295

ft)

10m

(33f

t)

PR-8

430

Plat

form

4 c

able

M12

-8 p

in, A

-cod

e, F

+MEt

hern

et, m

A, 2

4V

PR-8

430

Plat

form

4 c

able

M12

-8 p

in, A

-cod

e, F

+MEt

hern

et, m

A, 2

4V

PR-8

430

Plat

form

4 c

able

M12

-8 p

in, A

-cod

e, F

+MEt

hern

et, m

A, 2

4V

PR-8

660

Plat

form

4 c

able

ext

ende

rM

12-8

pin

, A-c

ode,

F+M

PR-8

431

Split

cab

le M

12M

12-8

pin

, A-c

ode,

FEt

hern

et (M

12-4

pin

, D-c

ode,

M)

mA,

24V

PR-8

431

Split

cab

le M

12M

12-8

pin

, A-c

ode,

FEt

hern

et (M

12-4

pin

, D-c

ode,

M)

mA,

24V

1m (3

ft)

PR-8

431

Split

cab

le M

12M

12-8

pin

, A-c

ode,

FEt

hern

et (M

12-4

pin

, D-c

ode,

M)

mA,

24V

1m (3

ft)

max

. 200

m (6

56ft

)

PR-8

680

M12

-8 p

in, A

-cod

e, F

Fiel

d pl

ugPR

-843

2Po

wer

sup

ply

and

mA

outp

ut c

able

Refr

acto

met

er o

nly

Cabl

es

M

MM

MM

M

F F F F

F

FF

Figure 2.2 mA and Ethernet output



2.3 Ethernet connection

The Ethernet connection enables data download from a refractometer to a computer.

Any type of computer (PC, Mac, mainframe...) with a compatible network connection

can be configured to view and download data from the refractometer. The refractome-

ter can be configured and monitored without any special software by using a standard

web browser. Chapter 8 gives all the specifications necessary towrite a data acquisition

program.

The connection on the Split cable PR-8431 is an industrialM12 connector. If connection

to a device that uses RJ45 is desired e.g. to connect with a laptop, Ethernet converter

cable PR-8442-001 is needed.

Figure 2.3 RJ45 network connection

Several refractometers can be connected to the same Ethernet network. Also, the re-

fractometer has an automatic function (known as Auto MDI/MDIX) to detect the po-

larity of the network so that the network may utilize either cross-over or straight inter-

connecting cables.

Figure 2.4 shows an example of how to connect three refractometers to an existing LAN

with a switch.



Hub/Switch

LAN

Ethernet Ethernetcable

24 VDC

24 VDC

24 VDC

mAoutmA

outmAout

Figure 2.4 Three refractometers in the same network.

It is possible to use a WLAN access point to decrease the number of cables (figure 2.5).

WLAN

Accesspoint

Ethernet

24 VDC

mAout

Figure 2.5 Connecting refractometer(s) via wireless.

The maximum distance of a single Ethernet connection is 100m (incl. one joint

adapter/coupler), but if longer distances are required, a fiber link may be used to

extend the range (see figure 2.6). The range may be up to several kilometers with a

suitable fiber connection.

mAout

24 VDC

FiberMediaconverter

Mediaconverter

Ethernet

Figure 2.6 Using fiber link to connect refractometer(s).



2.3.1 IP settings for the PR-43

All PR-43 refractometers are shippedwith the factory default IP address of 169.254.43.43.

This address belongs to the Zeroconf addresses (as defined in IETF standard RFC 3927)

so that it can easily be reached from a stand-alone computer, usually without changing

the network settings of the computer. This address will remain in the refractometer

even after a different IP address has been set. The refractometer answers in the address

that is first called up after startup.

Note: If there are more than one refractometer in the same network, this address

cannot be used (section 2.3.3).

The IP address of the refractometer can be changed through the refractometer home-

page (see Chapter 3).

2.3.2 IP settings for a stand-alone computer

Whena computerwith automatical IP settings (DHCPenabled) is turned on in a network

with only the refractometer, the computer should automatically obtain an IP address

169.254.x.x. In this case the factory default address of the refractometer can be used

for connecting without any further changes in settings. If this does not work, make

sure that the WLAN (Wireless network connection) is not active on the computer that

is connected to the refractometer. If the WLAN is active, the computer’s Ethernet con-

nection may not function as expected. Also, obtaining the 169.254.x.x. address may

take up to a minute.

If the connection to the refractometer still cannot be achieved, the computer’s IP ad-

dress can be checked by opening the command window (command prompt) and by

typing the command ipconfig at the command prompt (press Enter to give the com-

mand), see figure 2.7 (in Mac OS X and Linux the same command is called ifconfig).The information given will include the computer’s IP address. If the address does not

start by 169.254, the IP address of the computer needs to be configured manually to

e.g. 169.254.43.44, netmask 255.255.0.0.

For further troubleshooting, see section 2.3.5.

Note: The connectionwill notwork if the computer and the refractometer have exactly

the same IP address.

When the network settings of the refractometer (and/or the computer) have been con-

figured according to the instructions above, the next step is to test the connection as

instructed below in section 2.3.4.



Figure 2.7 Typical IP configuration for a stand-alone laptop when

connected to a refractometer; laptop wireless (WLAN) is turned off

2.3.3 Configuring a network of refractometers

In case there are more than one refractometer in a network, their IP addresses have to

be configured manually as the factory default will not work.

If the refractometer is to be connected to a factory network, consult the network ad-

ministrator for the correct settings.

If the network is a stand-alone network with only one refractometer and one or more

computers with no connection to any other network, then the IP addresses can be

chosen rather freely. One possibility is to number the refractometers so that they all

have 192.168.43.x addresses so that every computer and refractometer has a different

number x between 1...254. The subnetmask (or netmask) is in this case 255.255.255.0.

(see figure 2.8).

Hub/SwitchIP = 192.168.43.1

IP = 192.168.43.2

IP = 192.168.43.3 IP = 192.168.43.100netmask = 255.255.255.0

Figure 2.8 A network of PR-43s.



Note: There are no settings for subnet mask, default gateway or name servers in the

refractometer, as these settings are not required.

2.3.4 Testing the Ethernet connection

When the refractometer is connected to a switch, the corresponding link light should

light up in the switch.

Once the refractometer is powered up, it should be reachable from any correctly con-

figured computer. Typing the IP address of the refractometer to the address bar of a

web browser should bring up the refractometer homepage (see Chapter 3).

Note: The factory-default IP address of the refractometer is 169.254.43.43. This ad-

dress should always respond (see section 2.3.1).

2.3.5 Troubleshooting the connection

In case the refractometer cannot be reached through the network, check the following

things:

1. the refractometer receives power; the Ethernet switch link light is lit.

2. the network settings of the computer are compatible with those of the refractome-

ter (section 2.3.2)

3. if the refractometer should be at IP address 169.254.43.43, but cannot be reached,

check that there is only one refractometer in the same network, as otherwise there

is an address conflict

4. check that the software firewall of the computer does not block the connections

A useful test to determine whether the problem is in network settings is to set up a

small network. Perform the following steps:

1. set up a network of only one refractometer and one computer

2. check that the computer has suitable network settings and that its WLAN connec-

tion is turned off (section 2.3.2)

3. use the ping utility of the computer to try and reach the refractometer.



The ping utility mentioned above is available in Windows systems by using the Com-

mand Prompt (usually found in the Accessories; or open Run, type cmd in the empty

line and press enter to open Command Prompt). The usage of ping is very simple: go to

the command interface, type the name of the command and the IP address you want

to check and press Enter. If the Ethernet connection is physically working and the ad-

dress given to ping is correct, the refractometer will answer to ping and return any data

packets sent to it, see figure 2.9.

Figure 2.9 Pinging address 169.254.43.43,

ping returned fully and connection ok.



3 Web interface

Every PR-43 refractometer has a built-in web server with a homepage. The refractome-

ter homepage allows you to configure, monitor, verify and diagnose the refractometer.

Once a refractometer is connected, the homepage is accessed by simply entering the

refractometer’s IP address into the address bar of the computer’s web browser.

Opening the refractometer homepage:

1. Establish a functioning ethernet connection to the refractometer. For further de-

tails, refer to section 2.3.

2. Open your preferred web browser (for example Mozilla Firefox, Internet Explorer,

Safari, Edge or Chrome).

3. The address (URL) to access the refractometer’s homepage is the refractometer’s

IP address, which for a factory default set PR-43 it is 169.254.43.43. Type the IP

address in the browser address bar, then “enter”, just as you would enter any other

web address (for example http://www.kpatents.com/)

4. Wait until the homepage is loaded, this may take a few seconds.

The page looks approximately as in figure 3.1; the exact appearance of the pagewill

depend on which browser you are using and also screen settings.

5. Using the links in the link bar at the left side of the page you may access more

extensive refractometer information.

Important: The JavaScript support must be enabled in the browser, in order for the

web pages to function as intended.

3 Web interface 11


3.1 Main page

Once the refractometer homepage has loaded, it will display all the essential informa-

tion regarding the refractometer.

Figure 3.1 Main page

The main page shows the measurement values, serial number and the tag for the re-

fractometer. The small numeric display in the bottom right of the page indicates the

number of measurement cycles (one per second) since the last login to the refractome-

ter.

Figure 3.2 Measurement cycles

since last login



3.2 Diagnostics

The Diagnostics page (figure 3.3) displays the diagnostic values produced by the refrac-

tometer. In addition to the measurement results, the page shows several intermediate

results and other diagnostic values.

The optical images produced by the refractometer can be seen on this page. Both the

images and the diagnostic values are live values, updated with an interval of a few

seconds.

Figure 3.3 Diagnostics page

3.3 Parameters

All the refractometer’s functional parameters can be changed using the Parameters

page. The link to the Parameters page is located in the menu displayed on the right-

hand side of the computer display.

3 Web interface 13


Figure 3.4 Parameter page

Most parameters are changed by deleting the old parameter and writing a new one in

the field. Some, like e.g. temperature unit, are drop-down lists, click the little triangle

on the right to see the list and to change the parameter. When you have changed

a parameter, click the Submit changes button to apply the changes. The parameter

update may take a few seconds to apply.

If you have edited a parameter but not submitted the change yet, you can undo all

changes by clicking the Undo changes button. Note: The parameter changes are only

saved when you click the Submit changes button. If you make parameter changes, but

e.g. go to the Diagnostics page, the parameters are not changed and you’ll get the old

parameters.

3.3.1 Measuring field samples

The diagnostics page (figure 3.3) offers a possibility to measure samples for field cali-

bration purposes.



A sample can be measured by clicking the Field point button on the page. After clicking

the button the refractometer will measure the sample ten times and then it shows the

average and standard deviation of the measurements. Also the measurement status is

shown, and if the status is not Normal operation, the point will not be accepted.

Several points may be measured, and all the points are shown on the page until the

page is reloaded.

Figure 3.5 Measuring field samples

3 Web interface 15


3.3.2 Optical image

The raw optical image (figures 3.6 and 3.7) which contains all optical information can

be seen by clicking on the Optical image link on the right side of the Diagnostics page.

Figure 3.6 Raw optical image of a compact refractometer

Figure 3.7 Raw optical image of a probe refractometer



3.4 Verification

The refractometer verification can be performed on this page (figure 3.8). Follow the

instructions on the verification page to perform instrument verification.

Figure 3.8 Verification page

4 Startup 17


4 Startup

4.1 Startup

4.1.1 Initial check

Connect the refractometer, and check that it powers up properly (see section 2.3.4).

Use a web browser to open the refractometer homepage and check that the serial

number of the refractometer corresponds to that on the refractometer nameplate.

Check the parameters on the Parameters page and adjust them as needed (see sec-

tion 3.3). Remember to submit changes!

4.1.2 mA check

Measure the mA output. If the refractometer is not in the line (i.e. message is NO

SAMPLE), mA out sends default mA. The default mA and mA maximum and minimum

are set via web browser on the Parameters page (see section 3.3).

4.1.3 Calibration check

Wait until normal process conditions occur. The concentration reading is precalibrated

at delivery and a copy of the Refractometer calibration certificate is shipped with the

refractometer. If the diagnostic message is NORMAL OPERATION but the concentration

reading does not agree with the laboratory results, consult section 5.2, “Calibrating

the concentration measurement”.

4.2 Viewing refractometer status

The basic information on the measurements is shown on the main page of the refrac-

tometer (section 3.1). More information is shown on theDiagnostics page (section 3.2).

The measurement result is calculated from the refractive index (nD ) and process tem-

perature (T) values. Both of these values are on the main page.

In addition to these measurements, the refractometer monitors its internal temper-

ature and humidity, which both are available on the Diagnostics page. The internal

temperature should not be above 55 °C, and the humidity should be below 30 %.



5 Configuration and calibration

5.1 Configuring the refractometer

In PR-43, all parameter changes are made with a web browser through the Parameters

page, see section 3.3.

5.1.1 Signal damping

The system provides the possibility to enter signal damping to diminish the influence of

process noise. The damping is applied to the CONC value (and thus the output signal).

The PR-43 offers three types of signal damping. Exponential (standard) dampingworks

for most processes and is the standard choice for slow and continuous processes. How-

ever, if the process has fast step changes, linear (fast) damping gives shorter settling

time. Slew rate damping limits the maximum change for the output signal in one sec-

ond.

The damping time is set separately. What the damping timemeans in practice, depends

on the damping type:

In the exponential damping, the damping time is the time it takes for the concentra-

tion measurement to reach half of its final value at a step change. For example, if the

concentration changes from 50 % to 60 % and damping time is 10 s, it takes 10 seconds

for the refractometer to display concentration 55 %. A damping time of 5–15 seconds

seems to work best in most cases.

In the linear damping (fast damping), the output is the average of the signal during

damping time. After a step change the signal rises linearly and reaches the final value

after the damping time. Figure 5.1 shows how the damping time affects the measure-

ment.

The slew rate parameter is presented in output units. For example when the concen-

tration is measured in percentages, typical slew rate value is 0.05% to 1 %. It should be

noted that the slew rate limit damping is recommended for random noise suppression

as it is non-linear.

Note: The factory setting for damping in PR-43 is 5 s linear. Avoid overdamping, the

signal should not be made insensitive.

5 Configuration and calibration 19


40

41

42

43

44

45

46

47

48

0 10 20 30 40 50 60 70 80 90 100 110 120

Time [s]

CO

NC

[%

]

20 s

10 s5 s

Exponential damping

40

41

42

43

44

45

46

47

48

0 10 20 30 40 50 60 70 80 90 100 110 120

Time [s]

CO

NC

[%

]

30 s

15 s

7 s

Linear damping

Figure 5.1 Effect of damping time on measurement



0 10 20 30 40 50 60 70 80 90 100 110 120Time [s]

52

54

56

58

60

62

64

66

CO

NC

[%

]

0.05 /s

0.2 /s

0.5 /s

Figure 5.2 Effect of slew rate on measurement

5.1.2 Configuring mA output

The mA output values are set on the Parameters page (see section 3.3). Minimum and

maximum values set the measurement range. If your measurement unit is CONC% and

you want to measure the range 15–25 CONC%, the output signal for minimum 15 will

be 4 mA and for maximum 25 it’ll be 20 mA. Default mA sets an mA default output

value that the refractometer returns to in certain situations. The value can be set to a

low or high mA value, e.g. 3.0 mA or 22 mA.

Note: NAMUR is an international association of users of automation in process indus-

tries. The association recommendation NE 43 promotes a standardization of the signal

level for failure information. The goal of NE 43 is to set a basis for proactively using

transmitter failure signals in process control strategies. Using these failure signals, in-

strument faults are separated from process measurements.

NAMUR NE 43 uses the 3.8 to 20.5 mA signal range for measurement information, with

≥21 mA or ≤3.6 mA to indicate diagnostic failures (see figure 5.3). With that informa-

tion, it is easier to detect a failure condition on a refractometer, for example, it clearly

tells you whether you have an empty pipe or a failed instrument.



0 3.6

3.8

4 20

20.5

21

mA

failure OK

Measurement Data

failure

Figure 5.3 Default mA output values

The refractometer sends defaultmA if themessage isNOOPTICAL IMAGE, TEMPMEASUREMENT

FAULT, OUTSIDE LIGHT ERROR, NO SAMPLE or PRISM COATED.

An optional secondarymA output default can be set for NO SAMPLE state to differentiate

it from the other messages that cause the measurement to revert to default mA.

The factory setting for secondarymAdefault is factory set atDisable. To implement sec-

ondary mA default, go to themA output calibration section on the parameter page and

set secondary default mode to No sample and then set the mA output value desired.

Figure 5.4 Setting secondary mA default

5.1.3 Skip count

When the sample is removed, the refractometer goes to NO SAMPLE state. However,

if skip count is greater than 0, the CONC is frozen to its last value for the number of

measurement cycles (one per second) indicated by skip count.



Skip count is set in Output settings section of the parameter page.

Figure 5.5 Setting the skipcount value



5.2 Calibrating the concentration measurement

LAYER 1A parameters Refractometer nD calibration

Chemical curve

Field calibration

LAYER 2C parameters

LAYER 3F parameters

mA Output

CCD-camera Pt-1000

mA

nD

CALC

CCD

TEMP

TEMP

CONC

Figure 5.6 The layers of concentration

calibration

The concentration calibration is organized in 3 layers: the refractometer nD calibration,

chemical curve and field calibration. The advantages of the layer feature are free in-

terchangeability of refractometers, applications and recipes without any need for me-

chanical calibration adjustment in the field.

The optical image information is detected by the CCD-element and transformed into a

number (CCD). The process temperature is measured by a Pt-1000 resistance.



Layer 1: The refractometer calibration: The actual refractive index nD is calculated from

the CCD.

Layer 2: The chemical curve: The refractometer calculates the Brix or concentration

value based on nD and TEMP. The result is a temperature compensated calculated con-

centration value CALC.

Layer 3: Field calibration: Adjustment of the calculated concentration value CALC may

be required in order to compensate for some process conditions or to fit the measure-

ment to the laboratory results. The field calibration procedure determines the appro-

priate adjustment to CALC. The adjusted concentration is called CONC.

Output signal: The output signal is transmitted over the 4–20 mA current output or

through the Ethernet connection.

5.2.1 The chemical curve

The chemical curve is the theoretical concentration curve based on nD and TEMP. It is

defined by a set of 16 parameters.

A chemical curve is specific to the given process medium, e.g. sucrose or sodium hy-

droxide. The set of parameters is given by K-Patents and should not be altered, except

in case of changing to another process medium.

5.2.2 Field calibration

K-Patents provides a field calibration service that adapts the calibration to the factory

laboratory determinations based on the data supplied. The field calibration procedure

should be made under normal process conditions using standard laboratory determi-

nations of sample concentration.

Record the calibrating data on the PR-43 field calibration form (found in the end of this

manual), also available at <http://www.kpatents.com/> and by emailing a request to

<[email protected]>. Email (or fax) the completed Field calibration form to either

K-Patents headquarters or your local K-Patents representative. A computer analysis of

the data will be made at K-Patents and optimal calibration parameters will be sent to

be entered in the system.

For a complete report, 10–15 valid data points (see below) are needed. A data point is

of use for calibration only when the diagnostic message is NORMAL OPERATION.



Each data point consists of:

LAB% Sample concentration determined by the user

CALC Calculated concentration value

T Process temperature measurement in Centigrade

nD Actual refractive index nD

CONC Measurement in concentration units, the large size number

In addition to the calibration data, write down the refractometer serial number.

Accurate calibration is only achieved if the sample is taken correctly. Pay special at-

tention to following details:

− The sampling valve and the refractometer should be installed close to each other

in the process.

Warning! Wear protective clothing appropriate to your process when operating the

sampling valve and handling the sample.

− Run the sample before starting to collect data points to avoid sampling old process

liquid that has remained in the sampling valve.

− Read the values CALC, T(emp), nD and CONC at exactly the same time with sampling.

− Use a tight container for the sample to avoid evaporation.

Important: Offline calibration using process liquid very seldom gives reliable results,

as problems are caused by

− low flow which makes sample to form an unrepresentative film on the prism

− sample evaporation at high temperature or undissolved solids at low temperature

giving deviations from laboratory determinations

− an ageing sample which is not representative

− outside light reaching the prism

Thus calibration using the process liquid should always be made in-line.

The concentration measurement value can also be directly adjusted by changing the

field adjustment parameter f00.

The value of the bias parameter f00 will be added to the concentration value:

NEW CONC = OLD CONC + f00.



6 Troubleshooting

This chapter discusses refractometer error messages and other error conditions. To

view the error messages you need Web user interface WI or Compact user interface CI

orMultichannel user interfaceMI. The errormessages are visible on themain page/dis-

play on the user interface.

Note: A status message is always shown. However, message NORMAL OPERATION means

that there are no errors.

6.1 Hardware

6.1.1 Message HIGH INTERNAL HUMIDITY

Cause: Humidity measured inside the refractometer exceeds 60% relative humidity.

The reason may be moisture leaking in through prism seal or the cover being open.

Action: Please contact K-Patents.

6.1.2 Message HIGH INTERNAL TEMP

Cause: The temperature inside the refractometer exceeds 65 °C (150 °F). To read this

temperature, go to the Diagnostics page (section 3.2).

Action: See the refractometer specific manual about choosing mounting location and

cooling the refractometer head. It is also possible to cool the refractometer head with

a water cooled Cooling cover PR-14308.

6.2 Measurement

6.2.1 Message OUTSIDE LIGHT ERROR or OUTSIDE LIGHT TO PRISM

Cause: The measurement is not possible or is disturbed because outside light reaches

the camera.

6 Troubleshooting 27


Action: Identify the light source and block the light from getting to the prism at the

refractometer tip. The amount of outside light can be seen at BGlight on the diagnostics

page (section 3.2).

6.2.2 Message NO OPTICAL IMAGE

There are several possible causes to this message:

1. The prism is heavily coated. Remove refractometer from line and clean prismman-

ually.

2. There is moisture condensation in the refractometer, see section 6.1.1.

3. The refractometer temperature is too high, see section 6.1.2.

4. The light source is faulty. When the refractometer is removed from the process, the

yellow flashing light can be seen through the prism.

Note: The light is only visible at an oblique angle. Also check the LED value on

the Diagnostics page (section 3.2); if the value is clearly below 100, LED fault is not

likely.

5. There are negative spikes in the optical image. The probable cause is contamination

on the optical path. Please contact K-Patents.

6. The CCD card in the refractometer is faulty. Please contact K-Patents.

6.2.3 Message PRISM COATED

Cause: The optical surface of the prism is coated by the process medium or impurities

in the process medium.

Action: Remove refractometer from line and clean prism manually.

If the problem is recurrent, consider improving the flow conditions (see refractometer

specific manual for choosing mounting location). Automatic prism wash may also be a

solution.

6.2.4 Message LOW IMAGE QUALITY

Cause: The most likely cause for this message is coating on the prism. There still is a

optical image available, but the measurement quality may not be optimal.

Action: Clean the prism, see section 6.2.3 above.



6.2.5 Message NO SAMPLE

The operation of the equipment is OK but there is no process liquid on the prism. In

some cases this message may also be caused by coating on the prism.

6.2.6 Message TEMP MEASUREMENT FAULT

Indicates faulty temperature element. Please contact K-Patents.

Note: A difference to some other process temperature measurement is not a fault.

The refractometer shows the true temperature of the prism surface.

6.2.7 Concentration drift during NORMAL OPERATION

For drift upward or downwards to zero, suspect prism coating and clean the prism.

6.3 Diagnostic messages table

Important: The messages are listed in descending order of priority. Example: If both

NO OPTICAL IMAGE and TEMPMEASUREMENT FAULT are activated, only NO OPTICAL IMAGEwill be

shown.

Message Section

OUTSIDE LIGHT ERROR 6.2.1

NO OPTICAL IMAGE 6.2.2

TEMP MEASUREMENT FAULT 6.2.6

HIGH SENSOR HUMIDITY 6.1.1

HIGH SENSOR TEMP 6.1.2

NO SAMPLE 6.2.5

PRISM COATED 6.2.3

OUTSIDE LIGHT TO PRISM 6.2.1

LOW IMAGE QUALITY 6.2.4

NORMAL OPERATION

7 Principle of measurement 29


7 Principle of measurement

The K-Patents inline refractometer determines the refractive index nD of the process

solution. It measures the critical angle of refraction using a yellow LED light source

with the same wavelength (589 nm) as the sodium D line (hence nD). Light from the

light source (L) in figure 7.1 is directed to the interface between the prism (P) and the

process medium (S). Two of the prism surfaces (M) act as mirrors bending the light rays

so that they meet the interface at different angles.

L

P

MM

S

A C B

Figure 7.1 Refractometer principle

The reflected rays of light form an image (ACB), where (C) is the position of the crit-

ical angle ray. The rays at (A) are totally internally reflected at the process interface,

the rays at (B) are partially reflected and partially refracted into the process solution.

In this way the optical image is divided into a light area (A) and a dark area (B). The

position of the shadow edge (C) indicates the value of the critical angle. The refractive

index nD can then be determined from this position.

The refractive index nD changes with the process solution concentration and temper-

ature. For most solutions the refractive index increases when the concentration in-

creases. At higher temperatures the refractive index is smaller than at lower tempera-

tures. From this follows that the optical image changes with the process solution con-

centration as shown in figure 7.2. The color of the solution, gas bubbles or undissolved

particles do not affect the position of the shadow edge (C).



B BC CA A

Low concentration High concentration

Figure 7.2 Optical images

The position of the shadow edge is measured digitally using a CCD element (figure 7.3)

and is converted to a refractive index value nD by a processor inside the refractometer.

This value is used together with the measured process temperature to calculate the

concentration.

Figure 7.3 From image detection to concentration

8 Ethernet protocol specification 31


8 Ethernet protocol specification

The main purpose of the Ethernet connection is to collect measurement data from the

refractometer. For this data acquisition, you’ll need to have suitable software on your

computer. You can program a data acquisition program yourself following the specifi-

cations below.

For examples and ready-made applications, please contact K-Patents.

8.1 Communication protocol

The communications protocol is based on UDP/IP to port 50023. It is a client/server

protocol, where the refractometer is the server and thus only sends information when

the client (i.e. your computer) requests it. The server should answer to all requests

within 100 ms.

8.1.1 Request format

The client to server communication, i.e. the requests sent from your computer to the

refractometer, is in binary format. The request packets contain the following binary

data (all integers are in the network order, MSB first):

− 32-bit integer: packet number

− 32-bit integer: request ID

− (any): request data (depends on the request)

− (any): fill-in data

Important: The maximum size of the message is 1472 octets (bytes).

The packet number is echoed back by the refractometer, but not processed in any way.

The packet numbers do not have to be sequential, any 32-bit value is valid.

The request ID is a 32-bit value that identifies the requested function, for example

refractometer information. See section 8.2 for request IDs.

The request data consists of 0 to 1464 octets of additional data associated with the

request.

The fill-in data can be used to increase the number of octets in amessage. Any number

of NULL characters (0x00) may be added to the end of the request as long as the total



size of the message does not exceed the maximum of 1472 octets. This may be useful,

for example, if the client implementation uses fixed-length packets.

8.1.2 Response format

The response data sent by the refractometer is in ASCII format. With the exception of

the packet number, the data is human-readable. The data structure is very simple:

− packet number (32-bit integer)

− zero or more lines of ASCII (text) keys and values associated with these keys (for

example temperature key and process temperature in Celsius)

The packet number is echoed back without change. The client (software on computer)

can use the packet number to check the response against the packet number of the

request.

The message text consists of lines of text, each line a single key (of one word) and

its value or values. The values are separated from the key by an equal sign ( = ) and

multiple values are separated by a comma. White space (space or tabulator) is allowed

anywhere except within a single value or key name.

If the response consists of a character string, it is enclosed in double quotes (").

For example all these are valid message text lines:

ok

temp = 23.45

StatusMessage = "Normal Operation"

Note: All the key identifiers (see section 8.2 for additional information) are case-

insensitive. However, K-Patents recommends that they are written as in this specifi-

cation.

The server (refractometer) may send the response keys in any order. It will send the

mandatory keys (marked with an asterisk in section 8.2) of the specific request, but it

may omit any other keys. The server may also send keys that are not specified in this

document, but the client (computer) may ignore them.

8 Ethernet protocol specification 33


8.1.3 Request and response errors

When the server (refractometer) detects an error, it responds with an error message

(for more information see section 8.3). An error message can be caused for example by

an unknown request or inability to collect data for the mandatory keys of a response.

8.2 Request-response pair specification

The list below describes the query messages, i.e. request-response pairs, used for data

collection via Ethernet. Those response keys that are always sent are preceded by an

asterisk (*).

8.2.1 NULL message

The null message is included in the query messages for debugging purposes as it can

be used to check whether the server is listening. The message gives a high-level ’ping’

functionality.

Request ID 0x00000000Request data (none)Response key IP : IP address

MAC : Ethernet MAC address

8.2.2 Protocol version

The version query is responded with a value representing the server (refractometer)

protocol version.

Request ID 0x00000001Request data (none)Response key *Version : integer, the server protocol version (currently 3)



8.2.3 Refractometer information

The refractometerinformation query gives the basic information of the refractometer.

Request ID 0x00000003Request data 0x00000000 : always zero

Response keys *SensorSerial : string, refractometer serial number

*SProcSerial : string, processor card serial number

*SensorVersion : string, version number of the refractometer software

8.2.4 Measurement results

Themeasurement result query gives themeasured and calculatedmeasurement values

from the refractometer.

Request ID 0x00000004Request data 0x00000000 : always zero

Response keys Status : string, refractometer status message

PTraw : integer, PT1000 value

T : float, process temperature

8.3 Error message specification

If the server (refractometer) does not recognize the request or cannot fulfill it, it re-

sponds with an error message. The error message has the following keys:

*Error : integer, error code 0x00000000 : Unknown request

*Error : integer, error code 0x00000001 : Invalid request (request recognized,invalid request data)

*Error : integer, error code 0x00000002 : Invalid refractometer number

ErrorMsg : string, error details

There may also be error-dependent extra keys. Other error codes may be returned.

0x00000003 is to be handled as unknown request. Codes with higher numbers refer

to internal errors; contact K-Patents for more information on these.

A PR-43 refractometer field calibration form 35


A PR-43 refractometer field calibration form

Fill in this form and email (or fax) it to K-Patents Oy or to your local service representa-

tive. For contact information, please see http://www.kpatents.com/.

Refractometer serial no:

Customer:

Address:

Fax:

Email:

Sample description:

Solvent (water/other):

Laboratory method:

Date:

Data collected by:

Sample no LAB% CALC T nD CONC

For closer instructions, see section 5.2.2.



B EU declaration of conformity 37


B EU declaration of conformity

K-Patents OyP.O. Box 77FI-01511 Vantaa, Finlandtel. +358 207 291 570fax +358 207 291 [email protected]

K-Patents, Inc.1804 Centre Point Circle, Suite 106 Naperville, IL 60653, USAtel. (630) 955 1545fax (630) 955 [email protected]

K-Patents (Shanghai) Co., LtdRoom 1509, Tomson Commercial Building, No.710Dongfang RDPudong District, Shanghai, Chinatel. +86 21 5087 0597/0598fax +86 21 5087 0598

www.kpatents.com

Documents

Process Refractometer PR-43 Instruction Manual - K · PDF fileProcess Refractometer PR-43 ... P4-001 PR-43 REFRACTOMETER M-12-8 pin, A-code, M non-Ex PR-43 REFRACTOMETER ... tionisturnedoff(section2.3.2)